13/08/13 21:06:59.78 29/vYj8U0
Post-Chernobyl Thyroid Carcinoma in Belarus Children
and Adolescents:
Comparison with Naturally Occurring Thyroid Carcinoma in Italy and France*
URLﾘﾝｸ(jcem.endojournals.org)
Fig.6A,6B
＊Abstractから
Between 1986 and 1989, the number of thyroid cancer cases peryear
ranged from 3–8 and increased to 31 in 1990, to 66 in 1991, to
72 in 1992, to 93 in 1993, to 96 in 1994, and to 90 in 1995.
The age at diagnosis was 14 yr or less in 78.8% (children group) and more than
14, but less than 21, yr in the remaining subjects (adolescents group).
Mean (6SD) age at the time of the accident was 4.4 6 3.4 yr (3.2 6 2.3
in children and 8.9 6 2.7 in adolescents),
the majority of the patients (62.9%) being 5 yr old or less.
The time interval between the accident and the diagnosis (latency period) decreased progressively
from 7.5 6 1.6 yr in children 0–2 yr old at the time of the accident to 6.0 6 1.6
yr in those 9–11 yr old.
Since 1993, the yearly distribution of newcases showed
a decrease in the subjects 9 yr old or more at the time of the accident but
not in those 5 yr old or less.
This could not be
accounted for by a shift of exposed subjects to an age group at diagnosis
not included in this study, because
only subjects less than 12 yr of age at the time of the accident were considered in this analysis.
Mean age at diagnosis in Belarus patients was 11.3 6 3.1 yr (10.1 6 2.3 in children and 15.7 6 1.4 in adolescents), whereas,
among patients with naturally-occurring thyroid carcinomas from Italy and France,
the majority of cases were diagnosed after 14 yr of age (mean age at diagnosis: 14.6 6 4.2 yr).
The female-to-male ratio was significantly
higher in Italy and France (2.5/1), compared with the ratio of patients from Belarus (1.6/1).